Koopmans' Theorem in the ROHF Method: Canonical Form for the Hartree-Fock Hamiltonian Научная публикация
| Журнал |
Journal of Chemical Physics
ISSN: 0021-9606 , E-ISSN: 1089-7690 |
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| Вых. Данные | Год: 2006, Том: 125, Номер: 20, Страницы: 204110 Страниц : 10 DOI: 10.1063/1.2393223 | ||||||
| Ключевые слова | Computation theory; Electrons; Hamiltonians; Ionization; Theorem proving | ||||||
| Авторы |
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| Организации |
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Информация о финансировании (5)
| 1 | Российский фонд фундаментальных исследований | 06-03-32587 |
| 2 | Президиум РАН | |
| 3 | Региональный общественный Фонд содействия отечественной науке | |
| 4 | Совет по грантам Президента Российской Федерации | МК-4362.2006.3 |
| 5 | Совет по грантам Президента Российской Федерации | НШ-4821.2006.3 |
Реферат:
Since the classic work of Roothaan [Rev. Mod. Phys.32, 179 (1960)], the one-electron energies of a ROHF method are known as ambiguous quantities having no physical meaning. Together with this, it is often assumed in present-day computational studies that Koopmans’ theorem is valid in a ROHF method. In this work we analyze the specific dependence of orbital energies on the choice of the basic equations in a ROHF method which are the Euler equations and different forms of the generalized Hartree-Fock equation. We first prove that the one-electron open-shell energies εm derived by the Euler equations can be related to the respective ionization potentials Im via the modified Koopmans’ formula Im=−εm∕fmIm=−εm∕fm where fm is an occupation number. As compared to this, neither the closed-shell orbital energies nor the virtual ones derived by the Euler equations can be related to the respective ionization potentials and electron affinities via Koopmans’ theorem. Based on this analysis, we derive the new (canonical) form for the Hamiltonian of the Hartree-Fock equation, the eigenvalues of which obey Koopmans’ theorem for the whole energy spectrum. A discussion of new orbital energies is presented on the examples of a free N atom and an endohedral N@C60N@C60 (Ih)(Ih). The vertical ionization potentials and electron affinities estimated via Koopmans’ theorem are compared with the respective observed data and, for completeness, with the respective estimates derived via a ΔSCFΔSCF method. The agreement between observed data and their estimates via Koopmans’ theorem is qualitative and, in general, appears to possess the same accuracy level as in the closed-shell SCF.
Библиографическая ссылка:
Plakhutin B.N.
, Gorelik E.V.
, Breslavskaya N.N.
Koopmans' Theorem in the ROHF Method: Canonical Form for the Hartree-Fock Hamiltonian
Journal of Chemical Physics. 2006. V.125. N20. P.204110. DOI: 10.1063/1.2393223 WOS Scopus РИНЦ CAPlusCA PMID OpenAlex
Koopmans' Theorem in the ROHF Method: Canonical Form for the Hartree-Fock Hamiltonian
Journal of Chemical Physics. 2006. V.125. N20. P.204110. DOI: 10.1063/1.2393223 WOS Scopus РИНЦ CAPlusCA PMID OpenAlex
Даты:
| Поступила в редакцию: | 5 мая 2006 г. |
| Принята к публикации: | 17 окт. 2006 г. |
| Опубликована в печати: | 28 нояб. 2006 г. |
| Опубликована online: | 30 нояб. 2006 г. |
Идентификаторы БД:
| Web of science: | WOS:000242408100014 |
| Scopus: | 2-s2.0-33751563553 |
| РИНЦ: | 13510772 |
| Chemical Abstracts: | 2006:1306548 |
| Chemical Abstracts (print): | 146:69022 |
| PMID (PubMed): | 17144693 |
| OpenAlex: | W2089831956 |